Valuing the ecosystem services of the Chagos: a review of challenges and estimates

This study provides a preliminary review of the economic value of the ecosystem goods and services of the Chagos Islands, central Indian Ocean, in the period immediately prior to the designation of the Chagos marine reserve in April 2010. The goods and services valued include inshore and offshore fisheries, shoreline protection, scientific value, the islands' possible role in supporting southwest Indian Ocean fisheries and in southwest Indian Ocean reef recovery and its value as a unique and unspoiled ecosystem. The goods and services identified were largely intangible, with few associated directly with a market. Both the nature of the subject, particularly the significance of its non-use values and the uniqueness of the site, as well as incomplete data, presented valuation challenges. In order to accommodate these characteristics, estimates of annual economic flow were provided in addition to economic values. The study estimated possible annual economic flows of several hundred million pounds, with an economic value in excess of 1 billion (10 9 ), with the benefits accruing both regionally in the southwest Indian Ocean and globally.